SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = 'a826773d9e47bd6e65e7239a5ac8e45530a930e8ff35d6e3f676356f0cff93be' 
  AND token = 'gkU+VjHh3RrJrZBEQhK3WpoJz6UHOPXj+6IhdhLfco4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}